Jesus said of those who believe I give them eternal life and they shall never perish; no one can snatch them out of my hand (John 10:23) Clinched with two nails if you like. That illustrates a basic Christian teaching, which in theological terms, is called "perseverance of the saints". It's a very precious truth.
  It's got a different name nowadays. It's called "eternal security". But that subtle change in language, 'security' for 'perseverance' reflects what, I believe, is a dangerous change in emphasis. It reflects a basic change in teaching and a shift in emphasis on experience. Even more, it reflects the fact that the level of Christian commitment is woefully low today. We seem to have all but lost the knowledge of God as a holy God and we call sin by any other name, and so fail to see it for what it really is: an offence against God; an offence against a righteous and sovereign God, So many today call themselves "Christian" on the basis of some poorly understood experience. They decided they would become Christian. They make a once-for-all act of faith and claim themselves as secure.

I want us to look at Hebrews 12:14-29. For I believe the words speak into this situation. Here, I would say, we have words on the crucial work of God in conversion; on our response; then on our security, or better perseverance.
  Verses 18 to 24 would, I contend, speak to us of conversion. They make comparison of Mount Sinai and Mount Zion. Certainly they are telling us that the Christian need not live in fear; especially in fear of the written law on tablets of stone.
  But note they lie between 15 to 17, which warn us not to miss the grace of God, which tell us the lesson of Esau, who could bring about no change of mind (repentance, that is) and verses 28 and 29 which speak of receiving a Kingdom. As I've pondered these issues of conversion, commitment and perseverance, the Lord seems to have drawn me again and again to these verses, to what he does when he leads us to conversion. And remember it is he who brings us to conversion, to repentance and faith. By grace you have been saved through faith- and this not of yourselves...For we are God's workmanship, created in Christ Jesus to do good works which God has prepared in advance for us to do. (Eph 2:8,10)
  In these verses then we see Mount Zion and Mount Sinai, law and grace. The law came through Moses, grace and truth through Jesus Christ (John 1:17) But I believe that in the conversion process God takes us through law to grace. Thus in Galatians we read the law was a schoolmaster to lead us to Christ (3:24,KJV)- to lead us, to instruct us where, otherwise, we would be ignorant. So God leads us first of all through the law. He shows us the righteous demands of the law. He shows us that we fall so far short of his law that we cannot hope to keep it. He brings us to the point where we fall on our knees, begging for mercy.
  For God does nor just bring us to the law. he brings us to Sinai. He brings us to the mountain burning with fire. We hear such a voice speaking that those who (hear) it (beg) that no further word be spoken. We say with Moses "I am trembling with fear" The Lord leads us to the place of which Moses said "I feared the anger and wrath of the Lord , for he was angry enough to destroy you" (Deut 9:19)
  That, I would say, is the beginning of our conversion. But thanks and praise to God that he does not leave us there. For he shows us Mount Zion, the heavenly Jerusalem. We are shown that dread may be replaced with mighty ecstasy and w e long for it, but it seems to lack assurance and substance.
  But God also leads us to the 'church' (or assembly) of the first born whose names are written in heaven. He leads us to the assembly of true born-again believers. And he shows us Jesus. And what does he show us in Jesus?
  Jesus is the mediator of the new covenant. He shows us the One who is our surety. Therein lies the ground of our true security. For we have a covenant in the spiritual realm which is eternally and legally binding, in the Name of Jesus. We often actually miss this, but the covenant is between the Father and the Son The Sinai covenant was in these terms: This is the blood (for blood was the sine qua non of a covenant) of the covenant which the Lord has made with you (Exod 24:8) But that covenant was broken on man's side. At Sinai the people offered the blood of bulls. The new covenant is in the blood offered for us: the blood of the Lord Jesus Christ. This is my blood which is poured out for many (Matt 26:28)
  Then the sprinkled blood; through the blood of Jesus we have confidence to enter into the Most Holy Place (Heb 10:19) We can safely draw near in spite of that Mount which caused us such dread, for through the blood of Jesus that chasm between us and our Creator is bridged. Our sin, which was much more than the breaking of a written code, but an offence against the Holy One was laid upon the sinless Son of God. He who knew no sin was made to be sin for us that, in him we might become the righteousness of God (2 Cor 5:21) We shall never fathom the dread of that dark hour when all our sin and its offence was laid upon the LOrd Jesus Christ. The holy, sinless Son of God entered into the wrath before the fire of the Mount. Our hearts can but stand in awe and wonder and flow over in gratitude. So then, also:
  Jesus' blood speaks a better word than the blood of Abel. The Lord said to Cain "Your brother's blood cries out to me from the ground. Now you are under a curse" (Gen 4:10-11) But if the blood of Abel was a curse, the blood of Jesus is a blessing.

'Twas grace that taught my heart to fear
  and grace my fear relieved
 

Now I'm not trying to make the experience of salvation, of conversion, of re-birth a strait-jacket. Rather there is a divine sine qua non. Hugh Black wrote of salvation and described broken-ness at a Billy Graham meeting in the Kelvin Hall in Glasgow in the '50s. How much broken-ness is there today? Mr Black goes on to say that there is no human basis for salvation. He writes:

People come to you and say, "I want to become a Christian." And like a foolish person, you roll out the red carpet and say, "Well, that's just wonderful." Don't say, "That's just wonderful"- rather say, "And why do you, a hell-deserving sinner imagine that God should receive the likes of you."

Firstly, some refuse him who speaks- and the Greek word has a sense of rejecting. It's possible to say to this work of God in our hearts, "No! This is not for me." How terrible it is to turn away. It's the ostrich attitude of burying our head in the sand. For such a s do this, there is the terrible warning in Hebrews that there remains the fearful expectation of judgment and raging fire which will consume the enemies of God (10:27) Can we fail to sound the warning to those who think the things of God and his Christ are not for them? The Lord is patient; he does want all to come to repentance. But as Scripture warns: The Day of the Lord will come like a thief.

More significantly, there are those who, like Esau, are godless (v15)- and the word means that Esau had no true heart for God. I think we deal here with those who have touched the things of God, for Esau was by birth a natural inheritor of Abraham's blessing. But that was the point! He was the natural inheritor, he was not God's man. Jacob I loved, but Esau I hated (Rom 9:13) We deal with those who have never been truly converted. There are those who miss the grace of God; those for whom the things of God are but one of life's many distractions.
 So I would turn to verses 14 to 17. Let us note three points, three warnings

• a warning about those who are godless (v16)
• a warning about the 'bitter root' (v15)
• a warning about the loss of inheritance (v17)

Esau was a congenial fellow, a good hunter, and a man who loved his father, he would have made a fine neighbour, but he was not interested in the things of God.

Then, secondly, we are warned that it's possible to become victim of a "bitter root" (v15)- and "bitter" has more to do, not with bitterness, but with outright wickedness. For I see that you are full of bitterness and a captive of sin (Acts 8:23)
  Bitterness, wickedness can indeed grow like a root. It can be like a weed. And it's no use chopping a weed off at the surface. You have to get the root our, and how many weeds have deep, deep roots;and it's necessary to get the taproot out. And that can only be by the grace of God.

The third warning comes in verse 17. We read that Esau, having sold his birthright (when he was hungry and it was too much of a demand and too inconvenient); we read that when Esau wanted to inherit this blessing he was rejected. He could bring about no change of mind even though he sought the blessing with tears
  In verse 23 we read of the 'church of the first born' It was to the first born that a special inheritance belonged; the inheritance of a double portion. A double blessing is here in mind. All men receive the blessing of life- and if life sometimes doesn't seem much of a blessing, we need remember that we live in a world under the constraint of sin and lying under the control of the Evil One (1 John 5:19) But, even so, all have the blessing of life; only those whose names are written in heaven receive the double blessing of eternal life. What is written in heaven is not written because God changed his mind; it was written there before the foundation of the world.
  In Old Testament times, the double lot was the portion of the eldest son: which is what Esau forfeited, having no true hunger for the things of God. It's possible to touch and handle the things of God and then forfeit the blessing. We can't dabble in the things of the world and its uncleanness and then dip our toes in God's life-giving stream. It has to flow from within. It's possible to consider ourselves Christian; to deceive ourselves with worthless religion. The fruit of our lives is the true test.  True religion will keep itself unspotted from the world (James 1:27) Only with this inner conversion van there be true security; only then will we have a true hunger for the things of the Lord; only then will the root of bitterness (or wickedness) be truly cut out; only then are our names truly written in heaven; which is the true blessing. All else is burying our head in the sand.

It all devolves around the fact that where there has never been any sovereign work of God and his Holy Spirit there will be no true hunger for God; there will be that bitter, sinful root, And its tentacles will infiltrate and stifle us. Then some need, or, more likely, some passing want will rob us of our birth-right; we will in effect say, we no more want the things of God; they're too tiresome and restricting. Not that anyone suddenly 'gives up' Christianity; nearly always it's a slow erosion. Until joining in Sunday worship; meeting with fellow-believers; making time for prayer and study of Scripture go to the bottom of the queue. Other things become more important and absorbing. The things of God no longer seem to hold out any interest. You know, we always have time for what we feel is important; for what matters.
  Is this the case of any one of us? If it be so, let us not dally until we can bring about no change of mind; till tears cannot engineer the blessing. You cannot engineer this. You can seek the face and desire of the Lord whose mercy endures and who is gracious. Twice in these verses we are admonished; see to it; once make every effort;once see that

But I would end in verses 28 and 29
This is true security! True assurance! We rest in an don God's Word. We shall still know the reality of sin; the experiential separation from the world is never total; there are still sin, temptation, wickedness; there may be demonic strongholds. But with Paul we can say Not that I have already obtained this, or already been made perfect, but I press on to take hold of that for which Christ took hold of me (Phil 3:17) That is the saint's perseverance. Ultimately it rests with the One who took hold of us. For we are receiving a Kingdom.
  We rest on his promise; on the Lord's work in us. What blessed security! What true perseverance! For the perseverance is not just ours; first and foremost it is his!
  Those in the assembly of the first born. They are God's They are his workmanship, who will purify for himself a people who are his very own (Titus 2:14) God will persevere with all true saints to the very end; to the completion.
  We can depend on him. We are receiving a Kingdom that cannot be shaken. God's Kingdom will overcome all the kingdoms of this world. Why dally with them? No: let us be thankful indeed, full of true worship. Our God is a consuming fire. But his fire will not destroy. It will purge all dross. Welcome that fire gladly. God knows what he is doing with us. Sometimes it will hurt. Sometimes we will want to back off. But he will hold us and keep us. We have his promise. Look, as verse 2 says, at Jesus (fix our eyes on him) who endured the Cross, scorning its shame. We may feel very weak, very feeble, very sinful. Our burden of sin may feel, as Cranmer put it, intolerable. But trust the Lord. He will keep us. he will hold us, and one day our very eye will see him.

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